TECO L510 - Using PID Control for Constant Flow; Pressure Applications; What is PID Control?

9-1
9. Using PID Control for Constant Flow / Pressure Applications
9.1 What is PID Control?
The PID function in the inverter can be used to maintain a constant process variable such as pressure, flow,
temperature by regulating the output frequency (motor speed). A feedback device (transducer) signal is used to
compare the actual process variable to a specified setpoint. The difference between the set-point and feedback
signal is called the error signal.
The PID control tries to minimize this error to maintain a constant process variable by regulating the output
frequency (motor speed).
1、2
3、4
Positive
Negative
10-03
P(10-05)
I(10-06)
+
10-03
-
D
Target
10-00
Feedback
10-01
10-21
10-22
12-00, PID
Feedback Display
10-03=0
or external terminal
prohibit or stop
I Limiter
1、3
2、4
D(10-07)
+
+
Offset
(10-08
10-09)
+
Delay device
(10-10)
PID Communication
Read
Sleep /Wake
Function
PID Freq.
Output
2、4
1、3
10-03
I Reset
PID Limit
The amplitude of the error can be adjusted with the Proportional Gain parameter 10-05 and is directly related to
the output of the PID controller, so the larger gain the larger the output correction.